To See Pieces Of Halley’s Comet, Just Look Up!

Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Follow on Twitter @caleb_scharf.

Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Follow on Twitter @caleb_scharf.

It happens every year around now, and this year should peak on May 5th at approximately 9pm EDT (in the wee hours of May 6th if you’re on GMT). Little pieces of material that once belonged to the nucleus of Halley’s Comet will zip into our atmosphere as meteors.

The Eta Aquarids (so-called because the meteors appear to radiate from a direction on Earth’s sky close to the star Eta Aquarii in the Aquarius constellation) come from a dusty trail of material that probably separated from the comet several hundred years ago. Although Halley’s – a ‘short period’ comet that passes through the inner solar system every 75 or so years – isn’t going to hit the Earth in the foreseeable future, some of its filth does quite regularly.

In fact the Eta Aquarids are not the only bit of Halley muck the Earth encounters, the Orionids are usually even more potent, arriving in our skies in late October every year. Just like the Aquarids, these particles – some very tiny, some a little bigger – trace out, or stream, along what has been Halley’s orbital path. This highly elliptical trajectory passes close to our own orbit around the sun in two places – and thus we see a May meteor shower and an October one, roughly six months apart.

Halley's position over recent times, and in the near future - where its orbit intersects Earth's is where the meteor showers are seen (Credit: Steve Dutch, U. Wisconsin)

It’s a wonderful reminder of the dynamic and complex solar system that we live in. Go take a look if you can!

About the Author: Caleb Scharf is the director of Columbia University's multidisciplinary
Astrobiology Center. He has worked in the fields of observational
cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.)
Follow on Twitter @caleb_scharf.